Hub-integrated inflation system

ABSTRACT

A hub-integrated inflation system which functions to convert relative motion at the wheel end (e.g., between the axle and the hub or wheel) into a pumping motion. The relative motion is then converted into mechanical or electrical energy, which can be used to actuate a pump of an inflator.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/771,748 filed 27 Nov. 2018, U.S. Provisional Application No.62/792,830, filed 15 Jan. 2019, U.S. Provisional Application No.62/865,822, filed 24 Jun. 2019, and U.S. Provisional Application No.62/889,728, filed 21 Aug. 2019, each of which is incorporated in itsentirety by this reference.

TECHNICAL FIELD

This invention relates generally to the inflation system field, and morespecifically to a new and useful wheel-end inflation system in theinflation system field.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic representation of the inflation system.

FIG. 2 is a schematic representation of a variant of the inflationsystem, mounted to an example wheel end.

FIGS. 3A, 3B, and 3C are an exploded view of a hub example, an exampleof a hub body, and a cross-sectional view of a hub body, respectively.

FIG. 4 is a schematic representation of an example of a mechanicalvariation of the power pickup assembly.

FIGS. 5A and 6 are sectional and isometric views of an electricalgenerator variation of the power pickup assembly.

FIG. 7 is a schematic representation of an example of a hybridized powerpickup assembly.

FIG. 8 is a schematic representation of an example of an electricalgenerator variation of the power pickup assembly.

FIG. 9 is a schematic representation of an example of inflator componentlayout within an inflator example.

FIGS. 10 and 11 are schematic representations of a first and secondexample of selective engagement mechanisms, respectively.

FIGS. 11 and 12 and 13 are schematic representations of a first andsecond example of guide mechanisms, respectively.

FIGS. 14A-14D are schematic representations of an example of the thirdembodiment of the inflation system, a sectional view of the thirdembodiment installed on the hub, a sectional view of the spindle nutretention region, and a sectional view of the inflator retentionmechanism, respectively.

FIG. 15 is a schematic representation of an example of the firstembodiment of the inflation system.

FIGS. 16 and 17 are an isometric view and a sectional view of an exampleof the third embodiment of the inflation system, respectively.

FIG. 18 is a sectional view of an example of the first variant of theinflation system.

FIG. 19A and 19B are exploded views of a mechanical and electricalvariant of the third embodiment of the inflation system, respectively.

FIGS. 20A-20C are an isometric view, a sectional view from the back, anda sectional view from the front of an example of a fourth embodiment ofthe inflation system, respectively.

FIGS. 21 and 22 are examples of the power pickup assembly for the firstvariant of the inflation system.

FIG. 23 is an isometric view of an example of the sixth embodiment ofthe inflation system.

FIG. 24 is a schematic representation of an example of the power pickupassembly for the second variant of the inflation system, coupled to anexample of the sixth embodiment of the inflation system.

FIGS. 25 and 26 are isometric and sectional views of an example of theseventh embodiment of the inflation system.

FIG. 27 is a sectional view of a second example of the seventhembodiment of the inflation system.

FIGS. 28 and 29 are isometric and sectional views of an example of theeighth embodiment of the inflation system.

FIG. 30 is a schematic representation of an example of the inflationsystem with a mechanical power pickup assembly, an energy transmissionmechanism extending through a stud, and an example of the eighthembodiment of the inflation system.

FIG. 31 is a schematic representation of an example of the inflationsystem with an electrical generator power pickup assembly (e.g., withgenerator coils attached to the output component and a stator attachedto the bearing spacer), an energy transmission mechanism extendingthrough a stud, and an example of the eighth embodiment of the inflationsystem.

FIG. 32 is a schematic representation of an example of the inflationsystem with an electrical generator power pickup assembly (e.g.,cooperatively forming a permanent magnet generator, with an array ofpermanent magnets on the bearing spacer and a set of coils mounted tothe output component), an energy transmission mechanism extendingthrough a stud, and an example of the eighth embodiment of the inflationsystem.

FIG. 33 is a schematic representation of an example of the inflationsystem with a hybrid power pickup assembly, an energy transmissionmechanism extending through a stud, and an example of the eighthembodiment of the inflation system.

FIG. 34 is a schematic representation of an example of an electrical ETMextending through a stud.

FIGS. 35A-35D are sectional views of an example of the third variationof the inflation system.

FIGS. 36 and 37 are isometric and cutaway views of examples of fluidconnections.

FIG. 38 is a schematic representation of an example of a manifolddefined by stacked plates.

FIG. 39 is a schematic representation of an example of a manifolddefined by an annular ring.

FIG. 40 is a sectional view of an example of an inflation system with afloating cam.

FIG. 41 is an isometric view of an example of an inflation system with afloating cam.

FIG. 42 is a diagram of the cam angle for an example of the inflationsystem with a floating cam.

FIG. 43 is a diagram of an example of an inflation system with afloating cam.

FIG. 44 is a diagram of an example of an inflation system with asecondary actuator.

FIG. 45 is a diagram of an example of a floating cam motion about thebearing spacer with a different angular frequency than the hub body.

FIG. 46A is a diagram of an example of a two-lobed floating cam withdimples, where the cam follower passes over the dimples in the pumpingmode.

FIG. 46B is a diagram of an example of a two-lobed floating cam withdimples, where the cam follower engaged the dimple to transition thesystem from the pumping mode to the non-pumping mode.

FIG. 47 is a diagram of an example of the selective engagement mechanismwhere a cam follower is spaced apart from the follower surface of a cam.

FIGS. 48A and 48B are each sectional views of an inflation mechanism inthe bottom dead center position.

FIGS. 48C and 48D are each sectional views of an inflation mechanism inthe top dead center position.

FIGS. 49A and 49B are each sectional views of an inflation mechanism inthe bottom dead center position.

FIGS. 49C and 49D are each sectional views of an inflation mechanism inthe top dead center position.

FIG. 50 is a diagram of an example arrangement of cam followerengagement with a cam and a dimple.

FIG. 51A is a diagram of an example of a floating cam.

FIG. 51B is a diagram of the motion of a cam axis about the axis ofrotation.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following description of the preferred embodiments of the inventionis not intended to limit the invention to these preferred embodiments,but rather to enable any person skilled in the art to make and use thisinvention.

1. Overview.

As shown in FIG. 1, the hub-integrated inflation system 100 includes apower pickup assembly 110 and an inflator 120. The hub-integratedinflation system can additionally or alternatively include an energytransmission system 130, a tire connector 140, a selective engagementmechanism 150, an energy transmission mechanism 160, or any othersuitable component.

In variants, the inflator can include a housing, a pump 125, a mountingmechanism, an air inlet fluidly connected to the pump, an air outletfluidly connecting the pump to the tire, and a power pickup interfaceconnected to the power pickup assembly. The power pickup assembly caninclude an output component 114, statically mounted relative to theaxle, and an input component 112, statically mounted relative to thehub. However, the hub-integrated inflation system can include anysuitable set of components.

The hub-integrated inflation system functions to convert relative motionat the wheel end (e.g., between the axle and the hub or wheel) into apumping motion. The relative motion is then converted into mechanical orelectrical energy, which can be used to actuate the pump of theinflator.

2. Benefits.

The hub-integrated inflation system can confer several benefits overconventional tire inflation systems.

First, the hub-integrated inflation system can be integrated into (e.g.,built into, assembled into) the hub of the wheel, which can minimize theprofile and accessibility of the pump from the wheel exterior. This canfunction to reduce pump damage and theft. Variants integrating theinflation system into the hub can provide a facile end-user experience,with no end-user installation (e.g., the inflation system is built intoor assembled into hub) or one-time installation (e.g., after-marketinstallation). Variants integrating the inflation system into the hubcan additionally lower system exposure to damage resulting fromenvironmental or road hazards.

Second, variants of the hub-integrated inflation system can be specificto a given wheel end, such that the pressurized air is not centralized.This can minimize the complexity that arises from centralized tireinflation systems, such as managing complex components (e.g., rotaryfluid unions) and minimizing leak diagnosis and management complexity.Variants of the system can operate without an air pressure connectionand/or power connection to other vehicle systems (e.g., only a wirelesscommunication link to vehicle computers, no powered electricalconnection to vehicle, no electrical wiring to vehicle computers, etc.).

Third, variants of the hub-integrated inflation system can beautomatically controlled (e.g., based on pneumatics or tire pressure;using an automatic control system; etc.), manually controlled, orotherwise controlled.

Fourth, variants of the hub-integrated inflation system can improve theassembly and serviceability of tire inflation systems. Variants includea pump mounted radially on the hub body, allowing the pump to beaccessed/serviced without disassembly of the hub. Variants integratedinto the hub do not need to be removed and reattached every time thewheel is changed, which improves end-user experience and vehicleserviceability.

Fifth, variants of the hub integrated inflation system minimizecomponent wear, which can increase the lifetime of the system and/orreduce required maintenance. Variants have a no-slip condition atengaged bearing surfaces (e.g., cam follower e follower surface offloating cam, reference surface of floating cam on bearing spacer, etc.)when under load and a slip condition when unloaded (or experienceminimal loading due to component weight and/or inertia). Variants of thesystem have component contacts (e.g., cam follower contacting floatingcam, floating cam contacting bearing surface etc.) inside of a lubricantcavity (e.g., flooded with lubricant) to minimize component wearresulting from component contacts. Variants of the system decouplecomponents (e.g., cam follower contacting floating cam, floating camcontacting bearing surface etc.) during one or more modes of operation(e.g., pumping mode 500, non-pumping mode 510) to reduce component wear.

Sixth, variants of the hub integrated inflation system can reduce thenumber of components required, which can minimize weight, cost, andfailure points on the system. In some variants, the pump, cam follower,and/or floating cam operate as the selective engagement mechanism (SEM),so there are no additional actuators or components required for the SEM.

However, the hub-integrated inflation system can confer any suitable setof benefits.

3. Hub.

The hub-integrated inflation system can be used with a hub thatrotatably mounts one or more wheels or tires 145 to an axle 200 of avehicle (e.g., a truck, a car, etc.).

Components of the hub-integrated inflation system and/or externalcomponents (e.g., the axle) can define one or more axes. Axes definedcan include: geometric axes, motion axes (e.g. translation axes,rotational axes, etc.), and/or any other suitable set of axes. Forexample, each component (or combination thereof) can define a centralaxis. The central axis can be: a geometric central axis, a mass centralaxis (e.g., an axis extending through a center of mass of thecomponent), or any other suitable central axis. In another example, eachcomponent can define a rotational axis, wherein the component rotatesabout the rotational axis (e.g., axis of rotation). Different axes ofdifferent components can be aligned (e.g., coaxial), offset, parallel,orthogonal, skewed, or otherwise arranged.

The axle can include: an axle spindle 210, an axle shaft, axle housing,and/or any other suitable component. In variants, the axle can includethe hub. The axle shaft and/or spindle can be: static relative to thevehicle body (e.g., not rotate relative to the vehicle body, such as ina trailer axle), static relative to the wheel (e.g., rotate with thewheel) rotate relative to the vehicle body (e.g., axle shaft in a driveaxle), rotate relative to the wheel (e.g., not rotate with the wheel),or otherwise actuate relative to the vehicle or wheel.

The hub can include: a hub cap 270, a spindle nut 260 (and optionallyspindle nut retention 262), a spacer nut 280, a lock nut (or lock washer250), a hub body 160 (e.g., hub barrel, hub casing), an outer bearing240, an inner bearing 230, a bearing spacer 220, studs 290 (e.g., drivestuds) extending through stud bores defined in the hub body andmechanically connecting the hub to the axle, or any other suitable setof components (example shown in FIG. 3A).

The bearing spacer can be arranged in any suitable location. The bearingspacer preferably remains static relative to the axle spindle (e.g., isdirectly or indirectly mounted to the axle spindle), but can be arrangedin any other appropriate manner. The bearing spacer preferablycircumferentially surrounds the axle spindle (e.g., encircles the axlespindle) and has a central or rotational axis aligned with the axlespindle's central or rotational axis. The bearing spacer is preferablyarranged within the lubrication chamber, between the inner and outerbearings, but can additionally or alternatively be arranged outboard ofthe inner bearing relative to the axis of rotation, inboard of the outerbearing relative to the axis of rotation, and/or otherwise arranged. Thebearing spacer can have any suitable geometry. The bearing spacerpreferably has a convex outer surface (with an outer bearing diameter)and a concave inner surface (with an inner bearing diameter), but can beotherwise configured. The bearing spacer preferably defines an annularcross section (e.g., wherein the outer and inner surfaces definecircular cross sections), but can alternately have an arcuate outersurface with one or more lobes relative to the axis of rotation, have acircular triangular outer surface, have a changing cross sectionalarea/geometry (for an cross section orthogonal to the axis of rotation),have one or more grooves in the convex outer surface, and/or have anyother suitable geometry. The bearing spacer can be mounted in anysuitable way. Preferably, the bearing spacer is clamped between theinner race of the inner bearing and the inner race of the outer bearing(e.g., by the race sides, by the race arcuate surfaces), but canadditionally or alternately be clamped between the inner race of theinner bearing and a non-rotary component on the axle, and/or clamped tothe inner race of the outer bearing. The clamping force is preferablygenerated by a spindle nut, but additionally or alternately the bearingspacer can include an internal spring pre-loaded against one or moreinner bearing races, press-fit, mechanically bonded, and/or otherwisesecured.

The hub is preferably associated with an axis of rotation (rotationaxis), wherein the hub preferably rotates about the axis of rotation.The axis of rotation can be defined relative to the hub (e.g., a hubcomponent, such as the hub body or hub barrel), axle component (e.g.,axle spindle), external reference, wheel, tire, vehicle frame, vehiclesuspension, the ground, a driveshaft, and/or a different component.

In a first variation, the wheel mounted by the hub rotates about theaxis of rotation. In a second variation, the axle (e.g., axle spindle,axle shaft, axle component driven by the transmission, etc.) rotatesabout the axis of rotation. The axis of rotation can extend through: thewheel, the axle, the hub (e.g., hub body), the bearing spacer, thebearings, and/or any other suitable hub or axle component. The axis ofrotation is preferably coaxially aligned with or intersect the hub oraxle component's: geometric central axis (e.g., longitudinal axis), masscenter, or other component reference. However, the axis of rotation canadditionally or alternatively be offset the component reference.

In variants, the hub body can define a lubricant cavity (e.g., lubricantreservoir 310), wherein the bearing spacer is arranged within thelubrication cavity (example shown in FIG. 3B and FIG. 3C). Thelubrication cavity can be selectively fluidly connected to the ambientenvironment by a lubrication hole. The lubrication hole can extendradially through the hub casing from the hub interior to the hubexterior and defined along an axial portion of the hub (e.g., betweenthe drive studs and wheel studs; axially (relative to the axis ofrotation) through the hub cap; or be otherwise arranged. The lubricationhole can be fluidly sealed from the ambient environment by a lubricationcap. In variants, the fill hole can be modified (e.g., enlarged,machined out) and sealed using a cap, bolts, gaskets, membranes and/orany other appropriate components.

In variants, the hub body can interface with brakes, which function toslow the vehicle. Brakes can be mounted proximal to the wheel studs on aradially inner portion of the hub. Brakes can include a brake drum whichfits over the hub, and/or arranged in any other suitable manner.

Each hub-integrated inflation system can be connected to one wheel, twowheels, or any other suitable number of wheels (e.g., per wheel end).Each hub-integrated inflation system can be connected to one hub, ormultiple hubs. Each hub preferably includes a single hub-integratedinflation system, but can alternatively include multiple hub-integratedinflation systems. Each vehicle can include one or more hub-integratedinflation systems.

The hub-integrated inflation system can be integrated into the hub,retrofit into the hub, attached to the wheel (e.g., removably attached),or otherwise attached to the system.

The hub can be a steer hub, a drive hub, a trailer hub, or any othersuitable type of hub. The hub-integrated inflation system can be usedwith a front axle, rear axle, full-floating axle, semi-floating axle,three-quarter floating axle, non-floating axle, live axle, dead axle,lift axle, drive axle, steer axle, trailer axle, and/or any otherappropriate axle.

However, the hub can additionally or alternately include any suitableset of components in any suitable arrangement.

4. Inflation System.

The inflator of the hub-integrated inflation system functions topressurize air, and can additionally or alternatively form a component(e.g., output component) of the power pickup assembly, form a componentof the hub (e.g., a structural component, a retention mechanism, etc.),or perform any suitable functionality. Each hub-integrated inflationsystem can include one or more inflators or the same or different type.

One or more components of the inflation system operate relative to anaxis of rotation, which can be the same as (or coaxial with) the axis ofrotation of the hub or can be a different axis of rotation. The axis ofrotation can be defined relative to a hub component, axle component,external reference, and/or other component. Preferably, the axis ofrotation is defined relative to the axle spindle, but can additionallyor alternately be defined relative to the wheel, hub (hub body or hubbarrel), tire, vehicle frame, vehicle suspension, the ground, adriveshaft, and/or a different component. The axis of rotation can bedefined by component geometry (e.g., a boss, one or more faces/holes,axis of a hole, axis of an annular surface, etc.), motion of a center ofmass, and/or motion of a body (rotational and/or translational). Mostpreferably, the axis of rotation is the axis of the axle spindle, butcan additionally or alternately be the axis the wheel, the axis ofrotation of the wheel relative to the axle spindle, the axis of rotationof the hub body relative to the wheel, or otherwise defined.

The inflator can be arranged over the hubcap (and/or axle flange),replace the hubcap (and/or axle flange), be arranged proximal the hubcap(and/or axle flange), be arranged around the spindle nut (e.g.,concentrically about the spindle nut), be arranged between the hubcapand the hub barrel, be arranged within the lubricant reservoir, bearranged over the bearing spacer (e.g., concentrically about the bearingspacer), be coaxially arranged with the lubricant reservoir lumen, bearranged between the hub barrel and the brake, be arranged along theexterior of the hub barrel (e.g., between the drive studs, in the hubbarrel scalloping, along a face of the hub barrel, within the spacebetween the hub cap and the hub barrel, etc.), be arranged within thestuds, be arranged between the studs (e.g. extend axially along the hubexterior), replace the drive studs, be arranged within the lubricanthole 320, be arranged within new apertures formed through the hub barrel(e.g. holes formed axially, radially, arcuately, etc.), or otherwisearranged. The inflator can have an annular geometry, form a cap (e.g.,form a cavity or divot), have a cylindrical geometry, replace a hubcomponent, or have any other suitable geometry.

Components of the inflation system can be assembled through the rear ofthe hub, through the lubrication hole through the front of the hub,manufactured with the hub or hub components, or otherwise assembled intothe hub.

The inflator preferably includes a pump and a housing, but canadditionally or alternatively include an air inlet, an air outlet, apower pickup interface, an energy transmission mechanism, and/or anyother suitable component (example shown in FIG. 9). In an example shownin FIG. 9, the inflator can optionally include: a generator 430, anelectronics module 490, a hose connector 470, an intake filter 472, anexhaust filter and water handling unit 474, and/or any suitablecomponents.

The pump of the inflator functions to pressurize air. The pump ispreferably fluidly connected to the fluid source (e.g., ambientenvironment, via the air inlet), fluidly connected to the tire (e.g.,via the air outlet and/or tire connector), and mechanically orelectrically connected to the power pickup assembly. The pump ispreferably arranged inside of the inflator housing, but can additionallyor alternatively be arranged outside of the inflator housing or form theinflator housing. However, the pump can be otherwise connected to thehub-integrated inflation system components.

Each inflator preferably includes one or more pumps of the same ordifferent type, with the same or different arrangement.

The pump is preferably a piston pump with a chamber and piston (e.g.,actuating within the chamber along an actuation axis), but canadditionally or alternatively be a peristaltic pump, or be any othersuitable pump.

The piston of the piston pump can include a piston shaft connected to apiston head (as different components or the different parts of the samecomponent). Piston shaft actuation preferably translates the piston headalong the chamber length between an induction or intake stroke and acompression stroke, between a top dead center (TDC) position and abottom dead center (BDC) position, and/or between any other suitable setof strokes, positions, and/or modes. The piston shaft can be connected(rigidly or rotatably) to the piston, integrated from the piston,separate from the piston, integrated into the power pickup interface,and/or otherwise implemented.

The pump can be radially aligned with the hub (e.g., hub longitudinalaxis), axially aligned with the hub, aligned along a cord of the hub,skewed or offset from the hub, or otherwise arranged. In variants, thepiston shaft can extend radially outward relative to the axis ofrotation, but can additionally or alternately be skewed or otherwiseoffset. The pumping motion is preferably linear actuation, but it canalternatively or additionally be pneumatic or pumping motion.

In a first variation, the pump piston is directly or indirectlyconnected (e.g., via an energy transmission mechanism, via arotary-to-linear converter, via a motor 410) to the output component ofthe power pickup assembly (PPA). In this variation, the PPA ispreferably a mechanical PPA, but can alternatively or additionally be anelectrical generator PPA. In one example (example shown in FIG. 21), thepump piston can be driven by a motor via an intermediate gear set,wherein the motor can be powered by an electrical generator PPA. In asecond example, the pump piston can be directly connected to the PPA,wherein the piston shaft connects an output component of the PPA (e.g.,a cam surface, a cam follower) to the piston head.

In a second variation, the pump is electrically connected (e.g.,directly or indirectly, via an electricity conditioning circuit) to theoutput component of the power pickup assembly. In this variation, thePPA is preferably an electrical generator PPA, but can alternatively oradditionally be a mechanical PPA.

However, the pump can be otherwise configured.

The inflator housing functions to encapsulate and mechanically protectthe pump, and can additionally or alternatively define fluid manifolds,mounting points, or perform any other suitable functionality. Theinflator housing can be a single piece housing, a multi-piece housing(e.g., a two-piece housing), or be otherwise constructed. The inflatorhousing can be made of metal, plastic, a combination thereof, or anyother suitable material.

The inflator can optionally include one or more mounting mechanisms,which function to mount the inflator component(s) to the hub or wheelcomponent. All or a portion of the inflator components can be staticallymounted, movably mounted, entrained, and/or otherwise secured.Components which are not statically mounted can be: floating,constrained with less than 6 degrees of freedom relative to one or morehub components, partially constrained in one or more modes of operation,have different constraints between one or more operation modes, and/orbe otherwise configured. The inflator components can be retained orconstrained: axially, radially, arcuately, and/or otherwise constrained.In a first example, the cam follower is radially constrained relative toa follower surface of the floating cam in the pumping mode. In a secondexample, a floating cam is rotationally constrained (about the axis ofrotation) relative to the cam follower and/or hub body in thenon-pumping mode. In a third example, a floating cam is axiallyconstrained (e.g., along the bearing spacer longitudinal axis, by acollar or the walls of a groove, etc.).

Examples of the mounting mechanism can include bolts, studs, or anyother suitable fixturing mechanism. Additionally or alternatively, theinflator components can be mounted using an interference fit, adhesive,or any other suitable retention mechanism. Additionally oralternatively, the mounting mechanism can use existing hub retentionmechanisms (e.g. assembled into the inflator position at the hubassembly) to retain the inflator to the hub or wheel. Additionally oralternatively, the mounting mechanism can use: a channel(s) and/orboss(es) in a different component (e.g., groove or flange in the hubbody, piston shaft, cam follower, bearing spacer, etc. that the inflatorcomponent rests within), shaft collar(s) (e.g., on the bearing spacer),snap ring(s) (e.g., external on the bearing spacer, internal on the hubbody), guides mounted to the hub, spacer(s) (e.g., on either side of afloating cam), one or more pins (e.g., cotter pin, pin meshing with achannel in floating cam and/or bearing spacer, etc.) and/or any othersuitable retention mechanism.

The power pickup interface of the inflator functions to interface withthe power pickup assembly (PPA). The power pickup interface preferablyinterfaces with the output component of the PPA, but can additionally oralternatively interface with the input component of the PPA, form acomponent of the PPA (e.g., the output component, the input component),or be otherwise coupled to the PPA. For example, the housing can includean output gear 420, can include windings or magnetic elements, or caninclude any other suitable component of the power pickup assembly.

The power pickup interface is preferably connected to the pump, morepreferably the piston of the pump, but can alternatively be connected toany other suitable component.

The power pickup interface is preferably directly connected to the pump,but can additionally or alternatively be indirectly connected to thepump. The power pickup interface can be indirectly connected to the pumpby a rotary-to-linear converter, such as a crank or cam 102, or anyother suitable connection. Additionally or alternatively, the powerpickup interface can be connected to the pump via an electricalconnection, such as a wired or wireless connection. The power pickupinterface can be entirely located within the inflator, partially locatedwithin the inflator, arranged outside of the inflator (e.g. whereinpower is transmitted through the housing), or otherwise located.

The power pickup interface can be arranged on the inflator housing, suchas the interior surface, exterior surface, an end of the inflatorhousing, or any other suitable surface thereof; be arranged within theinflator housing (e.g., wherein the output component extends into theinflator housing); or be otherwise arranged.

The power pickup interface can include a cam follower 101 to transmitenergy from a rotary component (e.g., cam, floating cam) to the pump.The cam follower can be connected to the piston shaft, integrated intothe piston shaft, integrated into a peristaltic pump, and/or otherwiseconfigured. Each pump can be connected to one or more cam followers, andeach cam follower can be connected to one or more pumps. The camfollower preferably contacts and traverses along a follower surface of acam (acting as a bearing surface), but can additionally or alternatelycontact any appropriate surface on a PPA component. The cam follower canbe statically, rotatably, translatably, or otherwise coupled to thepump. The cam follower can be arranged radially inward of the followersurface (e.g., arranged within a channel, following a concave surface),be arranged radially outward of the follower surface (e.g., followingouter surface of a cam, engaging a convex surface), or otherwisearranged relative to the follower surface. The cam follower can beconstructed from a wear resistant material, a self-lubricating material(e.g., graphite impregnated, Teflon, nylon, Delrin, etc.), and/orotherwise constructed.

In a first variant, the cam follower includes a roller that rolls alonga cam surface (e.g., follower surface). The roller can be rotatablymounted to the pump-PPA connection (e.g., piston shaft) along theroller's rotational axis. The roller preferably engages with a no-slipcondition, but can alternatively engage with a slip condition, both ano-slip and slip condition, be controllable between a slip state andno-slip state, or be otherwise configured. In a second variant, the camfollower includes a slider that slides along a cam surface (e.g.,follower surface). In a first embodiment, the slider can translatewithin a groove defined in the cam surface. In a second embodiment, theslider can define a groove, wherein the cam surface (or portion thereof)slides within said groove. However, the cam follower can be otherwiseconfigured.

The inflator can optionally include an energy transmission mechanism(ETM), which functions to connect and/or transmit energy from the PPA tothe inflator when the inflator is not collocated with the PPA (e.g.,when the PPA is arranged within the hub interior, and the inflator isarranged exterior the hub). Examples of the energy transmissionmechanism include a drive shaft, a belt drive, wires, a rotary junction(e.g., replacing one or more of the hub bearings), or any other suitableenergy transmission mechanism. The ETM can extend through the shaft, astud (example shown in FIGS. 32 and 34), between the stud bores, througha radial surface of the hub barrel, through the inflator housing,through the lubrication hole, or through any other suitable component.In variants where the PPA or inflator is arranged within the lubricantreservoir, the ETM can optionally include bearings and/or seals thatfluidly seal the lubricant reservoir.

The inflator can optionally include one or more air inlets, whichfunction to provide unpressurized air (e.g., working fluid) to the pump.The air inlet preferably fluidly connects the air source to the pumpinlet, but can additionally or alternatively connect to any othersuitable set of end points. The air source is preferably the ambientenvironment, but can additionally or alternatively be a fluid reservoiror any other suitable fluid source. The inflator (e.g., pump) preferablypressurizes the air using energy converted from the relative motionbetween the hub and the axle, but can additionally or alternativelyconvert pressurized air using electricity or any other suitable energy.

The air inlet is preferably collocated with the pump, but canadditionally or alternatively be arranged distal the pump. The air inletis preferably defined by the inflator housing, but can additionally oralternatively be fluidly connected to the air source by a fluidmanifold. The fluid manifold can be defined by hub components, inflatorcomponents (e.g. the housing), tubing, or by any other suitablecomponent. The air inlet can optionally include valves (e.g., one-wayvalves, passive valves, active valves, etc.), membranes (e.g.,water-impermeable membranes, water-selective membranes), filters, or anyother suitable component.

The inflator can optionally include one or more air outlets, whichfunction to fluidly connect the pump outlet to the tire and to providepressurized air between (e.g., to and/or from) the pump and the tire.The air outlet can extend through the lubricant hole, through a newradial or axial access hole, through tubing routed to the tire andconnector, or through any other suitable fluid manifold. The air outletis preferably static relative to the inflator housing, but canadditionally or alternatively rotate relative to the inflator housing(e.g. include a rotary fluid connection, etc.).

The inflator can optionally include a generator, a battery or powerstorage, telematics, a control system, filters (e.g., intake and/orexhaust filters or water handling mechanisms), and/or any other suitablecomponent. These components can be housed in the inflator, or housed inseparate modules that are connected to the inflator.

The power pickup assembly (PPA) of the inflation system functions toharvest energy from relative motion (e.g. relative rotation) between theaxle and hub (e.g., between the stationary and rotary hub components,between the axle and inflator, etc.). The PPA can be positioned in anyappropriate location.

The PPA can be arranged at the wheel end (e.g., at the outer end of thehub), within the hub body, along the hub exterior (e.g., along an axialportion of the hub), at the hub interior, or at any suitable location.The PPA is preferably positioned between the inner and outer bearingsand/or circumferentially around the bearing spacer, but can additionallyor alternately be inboard of the inner bearing, outboard of the outerbearing, circumferentially around the inboard and/or the outboardbearing, and/or otherwise positioned in any appropriate axial and/orradial position relative to the axis of rotation. In a first variation,the PPA harvests energy from relative motion between the spacer nut (orlock ring) and the hub barrel (or wheel). In a second variation, the PPAharvests energy from relative motion between the bearing spacer and thehub barrel (or inflator, statically mounted to the hub barrel). In athird variation, the PPA harvests energy from relative motion betweenthe bearing cone and the bearing race. However, the PPA can harvestenergy from relative motion between any other suitable set ofcomponents.

Each inflation system can include one or more PPAs. Each hub, wheel, orwheel end can include one or more PPAs.

The PPA can be collocated with the inflator or be arranged distal theinflator. When the PPA is collocated with the inflator, the PPA can beadjacent or integrated with the inflator (e.g. wherein the hub or axlecomponent includes the first power pickup component and the inflatorincludes the corresponding or companion power pickup component).

When the PPA is arranged distal the inflator (e.g. wherein the inflatoris separated from the power pickup assembly by the hub barrel or othercomponent), the system can additionally or alternatively include an ETMwhich functions to transmit harvested motion or energy for the powerpickup assembly location to the inflator location. The ETM can include alinear drive, a belt drive, gearing, a piston, wires, or any othersuitable energy transmission mechanism. In one example, the ETM can berouted through the lubrication hole, the drive studs, or any othersuitable component from the hub barrel interior to the hub barrelexterior.

The PPA can include a static component and a rotary component (exampleshown in FIG. 2). The static component functions as an input component,and is preferably statically mounted relative to the axle (e.g.,directly mounted to the axle or mounted to an intermediate componentthat is mounted to the axle), but can alternatively be mounted to thehub. The rotary component functions as an output component, and ispreferably statically mounted relative to the hub (e.g., directlymounted to the hub or mounted to an intermediate component that ismounted to the hub), but can alternatively be mounted to the hub.However, the PPA can include any suitable set of components.

Examples of the input component include: toothed gears (e.g., externalgears; input gear; drive gear); toothed collars or flange edges; collarswith an array of windings, armatures, permanent magnets, and/or ferrouselements (e.g., ferrous teeth) arranged along the collar exteriordiameter; and/or any other suitable component. Examples of gears thatcan be used include: spur gears, helical gears, worm gears, bevel gears,or any other suitable gear.

Examples of the output component include: toothed gears (e.g., externalgears; internal gears; driven gear; complimentary gears to the inputgears); annular collars with an array of windings, armatures, permanentmagnets, and/or ferrous elements (e.g., ferrous teeth) along the collarinterior diameter; and/or any other suitable component.

The PPA can be mechanical (e.g., form a gear train), electrical (e.g.,be an electrical generator), a combination thereof, or be otherwiseconfigured.

In a first variation, the PPA is a mechanical PPA (example shown in FIG.4). In this variation, the input component includes an input gear ordrive gear, and the output component includes an output gear or drivengear (e.g., pinion). Both gears are preferably external gears, but eachgear can alternatively be an internal gear. The gear ratio between theinput and output gears can be: between 5:1 and 50:1, 10:1 and 30:1, be13:1, or be any suitable gear ratio. The PPA is preferably a directdrive but can additionally or alternatively be an indirect drive. ThePPA can include one or more bearing surfaces. Bearing surfaces (e.g.,wear surfaces) can be a region of contact between the component definingthe respective bearing surface and a secondary component. For example,the input component and output component can each define a bearingsurface. In another example, a PPA component and a non-PPA component(e.g., a vehicle component, the selective engagement mechanism, theenergy transmission mechanism, the inflator, etc.) can each define abearing surface. Bearing surface(s) can be lubricated (e.g., within thelubricant cavity, by supplied lubricant), un-lubricated, beself-lubricating (e.g., graphite impregnated, Delrin, Nylon, Teflon,etc.), or otherwise lubricated. Bearing surfaces can have no-slipconditions or slip conditions in one or more modes of operation. In afirst example, the bearing surface can be statically retained againstother component (e.g., exhibit a no-slip condition) in the pumping modeand translate relative to another component (e.g., exhibit a slipcondition) in the non-pumping mode (e.g., reference surface). In asecond example, the bearing surface has a no slip condition in thenon-pumping mode and a slip condition in the pumping mode. In a thirdexample, the bearing surface has the same surface condition in both thepumping and non-pumping mode (e.g., bearing surface of a cam follower,the bearing surface of the inner/outer bearing exterior, etc.). In afourth example, components (e.g., a cam follower) are only in contactwith a given bearing surface in each mode of operation. In anillustrative example of the fourth example, the cam follower contacts afirst bearing surface, such as a follower surface, during pumping mode;and contacts a second bearing surface, such as a stopper surface, duringnon-pumping mode.

The PPA can generate a torque about the axis of rotation (e.g., exertedon the axle spindle, bearing spacer, etc.; output by the PPA on theoutput component; etc.). The torque can be exerted by or on the axlespindle, the input component, the output component, the bearing spacer,an axle component, the hub body, the pump (or a component of the pump),and/or any other suitable component(s). The torque can be generated:from friction at one or more bearing surfaces, from mass imbalance, fromrelative motion between components, and/or from another source. In afirst example, torque is generated by an eccentric mass rotatingrelative to the wheel or hub. In a second example, the torque is resultsfrom a frictional force associated with a non-zero cam angle (e.g.,example shown in FIG. 42). In a third example, the torque iscollectively generated by friction and an eccentric mass. However, thetorque can be otherwise generated. The torque preferably opposes thedirection of rotation of the wheel about the axis of rotation, howevercan be in the same direction as the rotation, or can be negligible. Thetorque can be: 0 in-oz, 5 in-oz, 10 in-oz, 25 in-oz, 35 in-oz, 50 in-oz,100 in-oz, less than 50 in-oz, more than 50 in-oz, and/or anyappropriate torque.

The axle component can be the axle itself, be the bearing spacer, be thespindle nut, or be any other suitable component statically mounted tothe axle. The hub component can be the hub barrel (e.g., the interior ofthe lubricant reservoir), the hub body, the hub face, the hubcap, or beany other suitable hub component.

In the first variation of the PPA, relative rotation between the hub andthe axle rotates the rotor and generates electricity at the starterelectrically connected to the pump. In a second variation of the PPA,relative rotation between the axle and the hub rotates the output gear,which is mechanically connected to the pump e.g. via a rotary to linearconverter.

In a second variation, the PPA forms a generator (example shown in FIGS.5, 6, and 8). Examples of generators that can be formed include DCgenerators (e.g., homopolar generator, magnetohydrodynamic generators,etc.), AC generators (e.g., (induction generators, linear electricgenerators, variable-speed constant-frequency generators, flux switchinggenerators), or any other suitable generators. The PPA can be brushed orbrushless.

In this variation, the input component of the PPA includes a stator, andthe output component of the PPA includes a rotor. The rotor preferablyincludes the windings (e.g., field windings) and/or armatures, but canadditionally or alternatively include the ferrous elements (e.g.,ferrous teeth, permanent magnet array, field magnets, etc.). The statorpreferably includes the ferrous elements (e.g., ferrous teeth, permanentmagnet array, field magnets, etc.), but can additionally oralternatively include the windings (e.g., field windings) and/orarmatures. In one example, the input component can be the permanentmagnet of the lubrication reservoir (e.g., that collects metallic chipswithin the lubrication reservoir), wherein the output component can bewindings statically mounted to the static component (e.g., staticallymounted relative to the axle, such as mounted to the bearing spacer).However, the windings and ferrous elements can be otherwise arranged.

In this variant, the PPA can optionally include power conditioningand/or storage components that function to condition and store thegenerated electricity. The power conditioning and/or storage componentscan be located within the inflator, within the lubricant reservoir,external to hub barrel, or in any other suitable location. The powerconditioning and/or storage components can include capacitors,batteries, or any other suitable energy storage system.

In a third variation, the PPA forms a hybridized system (example shownin FIG. 7). In this variation, the PPA includes: a secondary outputcomponent 116 (e.g., electrical generator) with a stator staticallymounted relative to the hub and a rotor; an input gear staticallymounted relative to the axle; and an output gear connecting thesecondary output component (e.g., electrical generator's rotor) to theinput gear. Hub rotation about the axle rotates the secondary outputcomponent (e.g., electrical generator) about the axle's axis. Thiscauses the output gear to rotate about the input gear, thereby actuatingthe secondary output component (e.g., rotating the rotor of theelectrical generator).

In a fourth variation, the input component includes a plate 440 mountedat a predetermined angle to the axle axis, and the output component caninclude an idler arm 450. The predetermined angle is preferablynon-perpendicular to the angle axis (e.g., inclined at 30°, 60°, 90°,etc.), but can additionally or alternatively be perpendicular to theaxle axis. The plate can be statically angled (e.g., manufactured as asingular piece with the collar mounting the plate to the axle or bearingspacer), removably angled (e.g., include a plate biased against abearing spacer collar with an angled end, wherein the angled collar enddefines the plate angle), or otherwise retained in the angled position.The plate can have a flat face or a profiled face. When the plate has aprofiled face, idler arm arcuate translation across the plate faceaxially actuates (e.g., reciprocates) the idler arm; have a profiledperimeter, wherein idler arm movement along the plate perimetertranslates the idler arm radially or axially. Examples of the plate caninclude a swash plate, a wobble plate, a cam, or any other suitableplate. Examples of the idler arm include: a wheel, a pin, a slidingcontact, a gear, a hook or groove (e.g., that engages the plate edge, orany other suitable component.

In a fifth variation, the input component includes a cam mounted to theaxle (e.g., to the axle spindle). The cam can include an asymmetricarcuate surface and/or have an axis of rotation offset from the camcenter. The cam can be statically mounted relative to the axlecomponent, selectively retained relative to the axle component (e.g.,selectively retained relative to the axle spindle by a magnet, whereinthe cam is a magnetic cam; selectively retained relative to the axlespindle by a pawl or other mechanical engagement system; selectivelyretained relative to the axle spindle by the selective engagementmechanism; selectively retained relative to the axle component byfriction, such as between an inner cam surface and an outer surface ofthe axle component; etc.), and/or otherwise mounted relative to theaxle. In this variation, the pump can be mounted to the hub and bearranged radially, such that the pump piston can actuate radially (e.g.,mate with the cam's arcuate surface, mate with the follower surface).However, the pump can be otherwise arranged. In an example of pumpoperation, in the pumping mode, a magnet or other locking mechanismmounted to the axle (e.g., axle spindle) can selectively retain the camin a predetermined angular position relative to the axle (e.g., axlespindle), wherein pump rotation about the cam's arcuate surface drivespump actuation. The variation can be placed into the non-pumping mode byreleasing the cam from the retained position, such as by: removing powerto the magnet, physically actuating the magnet (e.g., axially away fromthe cam), using a clutch mechanism that forces the cam to rotaterelative to the spindle, by disengaging the cam follower from the cam,by releasing or reducing the force applied by the secondary actuator onthe cam, or otherwise placed into the non-pumping mode.

In a second example of the fifth variant, the cam (functioning as therotary to linear converter) is a floating cam (e.g., eccentric cam,hollow cam), examples of which are shown in FIG. 40 and FIG. 41. Thefloating cam is preferably rotatable relative to an axle component, avehicle component, a vehicle that rotates relative to a wheel, a wheel,the axis of rotation, and/or any other component. The floating cam ispreferably mounted to and rotates about a convex, arcuate surface of theaxle component (e.g., outer surface of the bearing spacer, a surfacewhich is static relative to the axle spindle), but can additionally oralternatively be mounted to any other suitable surface. In specificexamples, the floating cam can freely rotate relative to and beselectively couplable to the the axle (e.g., by cam follower pressure onthe cam arcuate surface; by secondary actuator 108 pressure on the cam;etc.).

The floating cam preferably defines a cam axis 106. The cam axis can bedefined relative to the geometry or motion (translational and/orrotational) of: one or more surfaces of the cam, cam volume, cam mass,one or more faces, one or more holes, the cam dimensions or geometry.Additionally or alternatively, the cam axis can be defined relative toany appropriate feature and/or in any other suitable manner. The camaxis preferably extends along the cam longitudinal axis (e.g., axialaxis), but can additionally or alternatively extend radially or in anyother suitable direction. The cam axis is preferably defined by thegeometric center of a surface (e.g., reference surface, followersurface) or aperture, but can additionally or alternately be defined bya center of mass. Alternatively, the cam axis can be defined by anypoint on the interior or exterior of the cam with any appropriaterelationship to the cam. Examples of the cam axis include: a geometriccentral axis (e.g., extending through center of the inner cam diameter,through the center of the outer cam diameter, etc.), a mass central axis(e.g., extending through the center of the cam mass), a rotationalcentral axis (e.g., extending through the cam's axis of rotation),and/or any other suitable cam axis. Preferably, the cam axis is parallelto the (hub or axle's) axis of rotation, but can additionally oralternately be skewed (e.g., angled, perpendicular, etc.) relative tothe axis of rotation. Preferably, the cam axis is offset from the axisof rotation, but can additionally or alternately intersect the axis ofrotation, be collinear (e.g., coaxial) with the axis of rotation. In aspecific embodiment, the cam axis is a reference axis parallel to theaxis of rotation (and offset from the axis of rotation) passing throughthe geometric center (point or line) of the reference surface of thefloating cam. In variants where the cam axis is offset from the axis ofrotation, the cam axis can trace a cam axis path 104 (example shown inFIGS. 51A and 51B). The cam axis path 104 can encircle the axis ofrotation, intersect the axis of rotation, or be otherwise related to theaxis of rotation. The cam axis path 104 can be: circular, roulette(e.g., cycloid, epicycloid, hypocycloid, spirograph, trochoid, involute,epitrochoid, etc.), harmonic, limacon, leminiscate, cardiod, and/or haveany other suitable shape.

The floating cam can define one or more bearing surfaces (e.g., wearsurfaces, contact surfaces) that function to engage with othercomponents. The bearing surfaces are preferably continuous, but canadditionally or alternatively be discontinuous. Different sections ofeach bearing surface is preferably of the same material, but canadditionally or alternatively be made of different materials withdifferent material properties (e.g., different friction coefficients,hardness, lubrication characteristics, etc.). Examples of the floatingcam bearing surfaces can include: a reference surface and a followersurface.

The floating cam preferably includes a reference surface 107 (e.g., aninner surface) which functions to engage the convex surface 108 (axlecomponent) in one or more modes of operation. The reference surface canhave any appropriate geometry. The reference surface is preferably aconcave surface of the floating cam (e.g., the inner arcuate surface ofthe floating cam), but can be otherwise configured. The referencesurface is preferably axially constant (e.g., does not vary in the axialdirection), but can additionally or alternatively vary in the axialdirection (e.g., taper inward, taper outward, etc.). The cross sectionof the reference surface (e.g., in a plane perpendicular the axis ofrotation) can be: circular, ovular, mirror the convex surface 108,and/or otherwise configured. For a cross section orthogonal to the axisof rotation, reference surface preferably has an inner radius (e.g.,largest inscribing circle in a cross section, smallest circumscribingcircle, average of inscribing and circumscribing circles, average radiusof curvature, radius of curvature, etc.) which is larger than the outerradius of the convex surface (e.g., by the same or different measure ofradius). The reference surface's inner radius is preferably larger thanthe convex surface's outer radius by a predetermined threshold (e.g., 1mm, 2 mm, 10 mm, 1%, 2%, 10%, 30%, etc.), such that the referencesurface is separated from the convex surface by a gap (e.g., thereference surface is coupled to the convex surface by a loose running,free running, easy running, close running, or sliding fit), but canadditionally or alternatively be equal to the inner radius, smaller thanthe inner radius, or otherwise related to the inner radius. Thereference surface is preferably symmetric (e.g., relative to the camaxis, relative to the axis of rotation, circular, annular, circulartriangle shaped, with one or more maximal radii, etc.), but canadditionally or alternately be asymmetric (e.g., eccentric about the camaxis, eccentric relative to a follower surface, etc.). The referencesurface can be magnetic (e.g., on the radial interior) or non-magnetic.

The floating cam preferably includes a follower surface 103 (e.g., anexterior surface) which functions to transmit energy from the floatingcam (input component of the PPA) to the output component of the PPA (camfollower) in one or more modes of operation. The follower surface canhave any appropriate orientation. The follower surface is preferablyarranged radially outward of the reference surface, relative to the axisof rotation, but can have any appropriate orientation. The followersurface is preferably a convex surface (e.g., outer arcuate surface ofthe floating cam), but can additionally or alternately be a planarsurface, a concave surface, and/or an internal surface. The followersurface can be a continuous surface or a discontinuous surface (e.g.,have a gap). The follower surface can be a single surface or a pluralityof surfaces. In a specific example, the follower surface includes afirst surface which is concave and a second surface which is convex,wherein the convex surface is positioned radially inward of the concavesurface, the cam follower selectively biased to follow the first surfacein a first mode of operation and the second surface in a second mode ofoperation. In a different specific example, a plurality of convexsurfaces of different radii are located at different axial positionsalong the cam axis. The follower surface can be magnetic (e.g., on theradial interior, on the radial exterior, etc.) or non-magnetic. Thefollower surface can have any appropriate geometry. The follower surfacecan be symmetric (e.g., reflectional symmetry and/or rotational symmetryrelative to the cam axis or the axis of rotation, etc.), but canadditionally or alternately be asymmetric (e.g., eccentric about the camaxis, eccentric relative to a follower surface, etc.). The followersurface can be circular, obloid, ellipsoid, triangular (e.g., a Reuleauxtriangle), lobed, arcuate (without dimples, with dimples, radiallysymmetric neglecting dimples, etc.), or otherwise configured. In aspecific example, the follower surface includes an arcuate surface whichdefines the path of the cam follower relative to the cam. In a variantof the specific example, the cam is dimpled (e.g., includes concavedivots in the follower surface, which can have the same or differentradius or chord length as the cam follower), such that the cam followerpasses over the dimple(s) in the pumping mode. In this variant, thefollower surface can be defined to include the dimple(s), define aplurality of follower surfaces separated by the dimples, define a singlefollower surface to include a theoretical section(s) spanning thedimple(s), and/or otherwise suitably define the follower surface. Thefollower surface can have: no lobes (e.g., circular), one lobe (e.g.,eccentric about cam axis, example shown in FIG. 43), 2 lobes (e.g.,diametrically opposed), 3 lobes (e.g., circular triangle shape, fixeddiameter, variable diameter, etc.), more than 3 lobes, and/or any othersuitable number of lobes. The follower surface can define a constantand/or variable cam angle (example shown in FIG. 42). The cam angle(along with other factors influencing friction such as: normal force,material properties, surface finish, lubrication, etc.) determines thefriction at the bearing surface between the reference surface and theconvex surface (bearing spacer). At a designated point on the followersurface, the cam angle is the angle between a vector orthogonal to thecam surface at the designated point and a reference vector passingthrough the designated point (e.g., orthogonal to the reference surface,orthogonal to the bearing spacer, orthogonal to the axis of thereference surface, orthogonal to the axis of rotation of the tire,etc.). Preferably, the cam angle is set such that there is a no-slipcondition at the bearing surface, is less than a threshold amount ofslip at the bearing surface, and/or satisfy any other suitable slip orfriction condition at the bearing surface. For frictional coefficient μand cam angle θ, this will occur according to the relationship: μ>tan(θ). This calculation can include additional adjustments for forcesresulting from mass eccentricity, opposing frictional force at the camfollower, a factor of safety, a margin of safety, and/or any otherappropriate adjustments. The cam angle can be: can be less than 1°, 1°,2°, 3°, 4°, 5°, 15°, 30°, 1-5°, 5-15°, 15-30°, greater than 30°, and/orany appropriate angle. In a first example, the follower surface is anouter arcuate surface of the cam. In a second example, the followersurface is defined by an arcuate channel within the cam (e.g., arrangedradially inward of the cam's outer arcuate surface), wherein the channelis of sufficient width and depth to allow the cam follower to bearranged radially inward of the follower surface (e.g., depth greaterthan or equal to the diameter of the cam follower). In the secondexample, the cam shaft extends radially outward from the cam follower tothe pump (e.g., through a circumferential gap in the arcuate wall of thecam, through a circumferential gap in the exterior of the cam followerof greater width than the piston shaft). In a third example, thefollower surface is arranged on a flange of the cam (e.g., on concaveinterior of the flange) with the cam follower arranged on radiallyinward of the flange.

The floating cam can have any appropriate mass distribution. The masscan be distributed uniformly by volume, non-uniformly by volume,uniformly about the cam axis, non-uniformly about the cam axis (and/oraxis of rotation), balanced, unbalanced, and/or otherwise configured.

The floating cam can engage the convex surface of an axle component(e.g., bearing spacer) in the pumping and/or non-pumping modes. In afirst variant, the floating cam ‘walks’ around the convex surface (e.g.,rotates around the convex surface at a different rate than the hub)during the pumping mode. Preferably, the angular frequency of thefloating cam is less than the angular frequency of the wheel about theaxis of rotation, but the angular frequency of the floating cam can alsobe the same or greater than the angular frequency of the hub. Therelationship between the angular frequency of the floating cam (ω_(Cam))and the angular frequency of the hub (ω_(hub)) can be represented by:

$\omega_{Cam} = {\omega_{hub} \cdot \left( {\frac{r_{1}}{r_{2}} - 1} \right)}$

where r₁ is the reference surface radius and r₂ is the radius of theconvex surface (e.g., bearing spacer), but can be otherwise representedor have any other suitable relationship. In a first example, the camaxis gyrates relative to the axis of rotation with ω_(Cam). This motionis preferably a circular motion (e.g., for a cam axis defined throughthe geometric center of the reference surface), but can additionally oralternately be a wavy or harmonic circular motion (e.g., for cam axisdefined through the geometric center of the follower surface). In thefirst variant, the bearing surface between the floating cam and thereference surface exhibits a no-slip condition during the pumping mode.In a second variant, the floating cam does not rotate relative to thehub body (ω_(Cam)=ω_(hub)) in the non-pumping mode of operation. In afirst example, the floating cam is mechanically retained (e.g., by theSEM, magnetically, by a dimple—an example is shown in FIGS. 46A-46B,static relative to the pump, etc.) relative to the hub body in thenon-pumping mode. In a second example, the bearing surface between thefloating cam and the reference surface exhibits a slip condition duringthe non-pumping mode. In a third example, the floating cam is staticallyretained relative to the bearing spacer (or other axle component) in thenon-pumping mode (e.g., by a magnetic force, by a secondary actuator109, etc.). In a fourth example, the floating cam freely rotatesrelative to the bearing spacer in the non-pumping mode (e.g., isretracted away from the bearing spacer; wherein a biasing mechanism thatbiases the floating cam against the spacer is released; etc.). However,the floating cam can be otherwise arranged in the pumping andnon-pumping modes.

The inflation system can optionally include a selective engagementmechanism (SEM), which functions to selectively control pump operationbetween a pumping and non-pumping mode. Selective disengagement canreduce drag on the wheel when not pumping, increase the lifetime of thepump, and/or confer any suitable set of benefits. Alternatively, thepump can be continuously engaged with the PPA. However, the pump can beotherwise connected to the PPA. The inflation system can include one ormore SEMs. Each SEM can be connected to one or more PPAs and/or pumps.

The selective engagement mechanism can selectively connect anddisconnect: the pump from the PPA (e.g., in the pumping and non-pumpingmodes, respectively, as shown in FIG. 47), the pump piston from thepump, the input component from the axle component (e.g., bearing spacer,axle), the output component from the hub component (e.g., hub body), theoutput component from the input component, the output component from thepump, the ETM from the pump, selectively freeze the pump (and/or camfollower) in a predetermined configuration (e.g. at top dead center 530,bottom dead center 520, compressed, expanded, etc.), or otherwiseselectively operate the pump between a pumping and non-pumping mode. Inone example, the SEM axially translates the output component away fromthe input component (e.g., inward or outward) to place the inflationsystem in the non-pumping mode (example shown in FIG. 10). In a secondexample wherein the input component includes a plate resting against anangled surface, the SEM can include actuating the plate to aperpendicular position (relative to the axle axis) to place theinflation system in a non-pumping mode (example shown in FIG. 11). In athird example, the SEM disengages the pump from a bearing spacer. In afirst specific example, the pump can be disengaged from the bearingspacer by disengaging a (floating) cam from the bearing spacer. In asecond specific example, the pump can be disengaged from the bearingspacer by disengaging a cam follower from a cam surface. However, anyother suitable component can be selectively connected or disconnected totransition between the pumping and nonpumping modes, respectively. TheSEM can bias the system towards engagement or away from engagement(e.g., default to the non-pumping mode). However, the SEM can otherwiseoperate the inflation system between the pumping and non-pumping modes.

The selective engagement mechanism can be automatic, manual, pneumatic(e.g. pressure driven), electrically-powered, magnetic, spring-driven,friction-based, and/or generate an engagement and/or disengagement forcein any suitable manner. Pneumatic SEMs can be controlled using pumpcharge pressure, tire pressure, and/or any other suitable fluid orpressure source. In one variation, tire pressure can be backflowed intothe pump (e.g., via active valve control, due to the tire pressureexceeding a cracking pressure of a passive valve, etc.) to pressurizethe pump chamber and bias the piston in a predetermined position (e.g.,bottom dead center). However, the SEM can include a pawl (e.g., thatselectively engages or disengages the input and output components in theconnected and disconnected modes, respectively), a clutch (e.g., thatselectively aligns and offsets the input and output components axiallyor radially in the connected and disconnected modes, respectively),sliding gears, rocker, synchromesh features, or any other suitableengagement and/or disengagement mechanism.

The SEM can operate the pump in a pumping mode when the tire pressure orreservoir pressure falls below of predetermined pressure threshold,and/or operate the pump in a non-pumping mode when the pressure exceedsa predetermined pressure threshold, or be otherwise controlled.

The selective engagement mechanism can be arranged within the inflator,between the inflator and the PPA, external the inflator, external theinflator system, or otherwise arranged.

The selective engagement mechanism can be electrically, mechanically,pneumatically, or otherwise controlled (e.g., connected anddisconnected). The SEM can be passively or actively controlled (e.g.,include active or passive actuation and/or return elements).

In a first variation, the SEM can electrically disconnect the pump fromthe PPA. In this variation, the pump can be electrically disconnectedfrom the power generator, and/or the generated power can be rerouted toan energy storage system, such as a battery. The SEM can be electricallyconnected/disconnected based on control instructions received from acontrol system, based on a signal generated from a tire pressure sensor,or otherwise controlled. The control instructions can be communicated tothe SEM from the control system via a wired or wireless connection, orbe otherwise received. Examples of the communication system include:802.11x, Wi-Fi, Wi-Max, WLAN, NFC, RFID, Bluetooth, Bluetooth LowEnergy, BLE long range, ZigBee, cellular telecommunications (e.g., 2G,3G, 4G, LTE, etc.), radio (RF), microwave, IR, audio, optical, wiredconnection (e.g., USB), or any other suitable communication module orcombination thereof. When a wired connection is used, the wiredconnection can be routed through the hub barrel, the drive stud, the hubbody, the lubricant hole, or through any other suitable path.

In second variation, the SEM can mechanically disconnect the pump fromthe PPA. The SEM can mechanically disconnect the power transfercomponents (e.g. disconnect the pump or inflator from the PPA;disconnect the output component from the output component; disconnectthe ETM from the pump or the PPA; etc.), disconnect portions of the pump(e.g., chamber from the piston), or disconnect any suitable set of powertransfer components. Examples of the mechanical SEM can include: aspring (e.g., biasing the components apart from each other, biasing thecomponents toward each other), a magnet, pneumatic pressure (e.g., frompump, tire, etc.; controlled by one or more passive or active valves),and/or any other suitable mechanical mechanism.

In one example, the input gear can be disconnected from the output gear.In a second example, rotor can be disconnected from the stator. In athird example, the idler arm can be disconnected from the plate. Infourth example, the piston and the cam follower can be disconnected(e.g., retracted) from the cam (e.g., by venting the charge pressure ofthe pump). However, any other suitable PPA component can be separated ordisconnected from any other suitable PPA component.

The power transfer components can be disconnected: axially (e.g., slidaxially in or out to axially misalign the components), radially (e.g.,actuated radially outward to disengage or inward to freeze thecomponents), arcuately (e.g., arcuately misalign the components), orotherwise disconnected (and reversed to reconnect). The power transfercomponents can be separated using pneumatics (e.g., using apneumatically-controlled mechanical actuator; selectively controlled byan active valve fluidly connecting a pressurized fluid source, such asthe tire, to the SEM; venting a charge pressure left within the pumpafter pressurized fluid egress; etc.), using an electrically controlledmechanical actuator, or using any other suitable actuation mechanism. Inthe first embodiment, the SEM mechanically disconnects the powertransfer components using the pump (e.g. the static position of the pumppiston is biased in a predetermined position, such as radially inward,by backflowing tire air into the pump; the pump piston is biasedradially outward by venting the charge pressure; etc.). In a secondembodiment, the SEM mechanically disconnects the power transfercomponents using a clutch (e.g. selectively connecting or aligning therotational axes of the power transfer components, etc.). The clutch canbe electrically or pneumatically actuated. In a third embodiment, theSEM mechanically disconnects the power transfer components using anaxially actuating arm (e.g. pneumatically actuated by the tire pressure,actuated by a motor, etc.) that actuates along the axle axis.

Disconnecting the pump from the PPA can additionally or alternatelyoccur based on binding friction, whereby the SEM controls the normalforce and associated friction exerted between a power transfer component(e.g., floating cam) and an axle component (e.g., bearing spacer, convexsurface). The binding friction disengagement mechanism can operate witha cam having any appropriate mass distribution (eccentric mass or noeccentric mass), a symmetric cam, and/or an asymmetric cam. Bindingfriction can be used with or without an active friction mechanism (e.g.,secondary actuator 109, pump piston operating as part of SEM). Thenormal force is preferably larger in the pumping mode (e.g., resultingin a no-slip condition which transfers torque from the axle component tothe power transfer component) than in the non-pumping mode (e.g.,resulting in a slip condition, disengaging torque transfer between theaxle component and the power transfer component).

Binding friction can be mediated by a geometric engagement mechanism. Ina first variation, the geometric engagement mechanism mediating bindingfriction can be one or more dimples on a cam. During the non-pumpingmode, the cam follower extends into the interior of a dimple, whereinthe normal force between the cam follower and the cam directly resultsin rotation of the cam about the axis of rotation (disengaging the camfrom the no-slip condition at the reference surface, thereby mediatingthe friction at the reference surface). The dimple is preferably locatedat the arcuate region of the cam corresponding to the bottom dead centerof the piston stroke (e.g., minimum distance between follower surfaceand reference surface on the cam), but can additionally or alternatelybe located at the arcuate region corresponding to the top dead centerand/or any other appropriate location on the cam. The SEM preferablyincludes one dimple for each lobe of the cam, but can alternativelyinclude more dimples than lobes, or less dimples than lobes. Dimples canbe used with one or more stoppers, the stopper preventing a cam followerfrom bottoming out at the full depth of the dimple (which would increasethe normal force between the cam and the bearing spacer—the resultingfriction preventing the cam from slipping on the bearing spacer). Thestopper may bound the range of travel (in a radially inward and/oroutward direction relative to the axis of rotation) of the piston head,piston shaft, and/or cam follower relative to the cam. The stopper maybe non-deformable (hard stop) or deformable (e.g., spring, rubber). Thestopper can be: a set of flanges (e.g., cooperatively defining a neckthat the piston shaft extends through, wherein the piston can includecomplimentary flanges that engage the stopper flanges), a spring, amagnet, and/or any other suitable stopping mechanism. The geometricengagement mechanism can alternately be a paired set of convex andconcave surfaces, where the cam follower contacts the convex surface inone operating mode (e.g., pumping) and the concave surface in a secondoperating mode (e.g., non-pumping). However, the dimples and/ormechanical SEM can be used with any other suitable separation controlmechanism.

Binding friction can be used with active friction control. In a firstembodiment, active friction is controlled by pressurizing the pump to acharge pressure (e.g., with air from the tire) increasing the forcebetween the cam follower and the cam (and thereby controlling the normalforce between the cam and the bearing spacer). In a second embodiment,the SEM includes an active friction member (e.g., separate piston,solenoid, roller, etc.; an example is shown in FIG. 44) which isseparate from the pump, that engages a flange on the cam or actuatingthe pump in a radial direction.

However, the power transfer components can be otherwise disengaged.

In a fourth embodiment, the SEM includes a gear disengagement mechanism.In a first example, the SEM can include a set of biasing mechanisms,including a first mechanism biasing the PPA components toward anengagement position (e.g., default position; e.g., by a spring), and asecond mechanism biasing the PPA components away from the engagementposition (e.g., by a pneumatic mechanism). The first and/or secondmechanisms can include: a pneumatic mechanism (e.g. fluidly connected tothe tire or pump pressure. etc.), spring, or other biasing mechanism.

In a second example, the gear disengagement mechanism can include a setof sliding gears, wherein the gears of the PPA slide relative to eachother (e.g. axially, such as in a transmission). However, the geardisengagement mechanism includes a rocker arm (e.g. actuating radially,along a chord, etc.), a synchromesh feature, a friction drive, or anyother suitable disengagement or engagement mechanism. However, the PPAcomponents can be otherwise engaged and disengaged (e.g., using any ofthe systems discussed above). However, the SEM can be otherwiseconfigured.

In variants where the output component can be disengaged from the inputcomponent, the PPA can optionally include a guide mechanism 118 thatfunction to guide input component-output component engagement and/ordisengagement (examples shown in FIGS. 12 and 13). The guide mechanismcan include an input-side mechanism, an output-side mechanism, and/orany suitable set of components. The input-side mechanisms and/oroutput-side mechanisms can be arranged along the: face of the inputcomponent or output component, the crest of the input or outputcomponent (e.g., crest of the gear tooth, be a partial tooth), or beotherwise arranged. The guide mechanism (e.g., input-side andoutput-side mechanism pairs) can include: a friction plates, a groove ortrack coupled to a cone or an out-runner wheel (e.g. deformable, rigid,etc.), be the input or output component itself (e.g. deformable gear),or any other suitable guide mechanism.

In systems with multiple distributed pumps, the inflation system canoptionally include fluid connections 460 fluidly connecting the pumpstogether. The fluid connections can define pump interconnections thatconnect the pump inlets and/or outlets together (e.g., in series, inparallel, a combination thereof, etc.). The fluid connections canoptionally fluidly connect the pumps to the working fluid source (e.g.,ambient environment), the tire, or to any other suitable endpoint. Thefluid connections can be mounted to the hub end, the hub face, thehubcap, and/or any other suitable location. The fluid connections canextend arcuately, radially, axially, or in any other suitable directionrelative to the hub face and/or axle axis.

In a first example, the fluid connections include tubing.

In a second example, the fluid connections include a manifold 190,statically defining inter-pump manifolds, inlets, outlets, and/or anyother suitable set of fluid connections (example shown in FIG. 38). Themanifold can be formed, manufactured by casting, 3D printing, stackingplates (with channels defined along the plate faces) together (e.g., bybrazing the plates together, compressing the plates together, etc.), orotherwise manufactured. Additionally, or alternatively, the manifold canbe formed by the hub or hub cap.

In a third example, the fluid connections can be cooperatively definedby an annular o-ring manifold that fits and seals to the inner diameterof the hub (example shown in FIG. 39). In this example, the o-ringmanifold cooperatively defines separate air channels for intake,exhaust, storage, and/or any other suitable fluid connection between themanifold and the inner hub diameter. In this variation the plate can besplit and assembled around the bearing spacer from the back of the hubbefore inner bearing assembly, can be manufactured with the bearingspacer as a singular piece, or otherwise manufactured. This variationcan optionally include a SEM. SEM can selectively disengage the outputcomponent from the input component (e.g. plate) by moving the pistons toa compressed position, moving the plate axially away from the pistons,moving the plate to a position perpendicular to the axle axis orotherwise selectively engaging or disengaging the PPA components.However, the inflation system can be otherwise configured.

The hub-integrated inflation system can optionally include a tireconnector. The tire connector functions to connect the air output to thetire. The tire connector can fluidly connect the air output to the tireby tubing, rigid manifolds or any other suitable fluid connection. Thetire connector can extend through the shaft, the stud, between the studbores, through the radio service of the hub barrel, through the inflatorhousing, through the lubrication hole, or through any other suitablecomponent of the hub. The tire connector can optionally include a hoseguard or any other suitable reinforcement. In one example, the tireconnector includes tubing connected to the tire with a Schrader valve.However, the tire connector can be otherwise configured. Each inflationsystem can include one or more tire connectors, fluidly connected to oneor more tires per wheel end.

5. Inflation System Variants.

In a first variation of the hub-integrated inflation system, theinflation system harvests relative motion between the spindle nut(and/or lock ring) and the hub body or wheel (example shown in FIG. 18).This variation can be particularly well suited for steer hubs, but canbe used with any suitable hub type. In this variation, the spindle nutfunctions as the input component, and a wheel-mounted component at theouter wheel end (e.g., the hub cap, the hub, the wheel, the inflator,etc.) functions as the output component (examples shown in FIGS. 21 and22).

In this variation, the input component can be arranged on (e.g.,retrofitted onto, manufactured as a singular piece with) the spindle nutor lock ring (e.g. the flange of the spindle nut, etc.). The inputcomponent can include exterior gear teeth arranged along the flange edgeor perimeter, magnetic elements arcuately distributed about the flangecircumference (e.g. evenly distributed, unevenly distributed), a flangewith a profiled perimeter (e.g., non-circular flange), a profiled flangewith an angled or profiled face, a cam integrated along the flange face,or any other suitable input component. In this variant, the inputcomponent preferably has the same diameter as the standard spindle nut,but can additionally or alternatively be larger or smaller than thestandard spindle nut, or have any suitable size. In some variants, aspindle nut having diameter larger than a standard spindle nut diametercan be preferable to bring the engagement between the input componentand the output component to the outside of the hub, likely requiringless modification to the hub.

In this variation, the output component is preferably statically mountedrelative to the wheel, and can be directly mounted to the inflatorhousing, to the hub cap, to the inner diameter of the wheel, to the hubbody interior (e.g. along the inner diameter of the outer end of the hubbody), or otherwise arranged. The output component can be an exteriorgear, but can additionally or alternatively be a set of windings, aferrous element, or any other suitable output component. The outputcomponent can be manufactured as a singular piece with the hub,manufactured as a singular piece with the hub cap, assembled into theinflator housing, retrofit onto the hub (e.g., using adhesive, aninterference fit, a mechanical retention mechanism, etc.), or otherwiseassembled into the system.

In a first embodiment, the inflation system leverages the firstvariation with the inflator mounted to the wheel face (e.g. to thespokes of the wheel) (example shown in FIG. 15). The pump can extendradially along, or parallel with, the wheel face. The output componentis preferably mounted to the interior diameter of the hub body, ispreferably axially aligned with the spindle nut or lock ring. Thisembodiment can optionally include an ETM (e.g., driveshaft) that extendsradially through the hub body from the output component (e.g., hubinterior surface) to the pump. The ETM can optionally include a bevelgear or rotary junction arranged between the inflator and the PPA.

In a second embodiment, the inflation system leverages the firstvariation with the inflator mounted to a hub axial surface (e.g., alongthe hub exterior; along the hub exterior between the inner and outersets of studs; between the studs; within the hub scalloping; etc.). Theinflator is preferably axially aligned with the spindle nut, but canalternatively be axially offset from the spindle nut. The inflator canbe mechanically or electrically connected to the output component via adirect drive wherein the spindle nut extends through the hub body, or beindirectly connected by an ETM extending through the hub body.

In a third embodiment, the inflation system leverages the firstvariation with the inflator mounted the hub end (examples shown in FIGS.14A-14B, 16, 17, and 19A-19B). In this embodiment, the inflator canfunction as the hubcap, form an annulus circumferentially surroundingthe hub end (e.g., spindle), or be otherwise configured. In thisembodiment, the inflator can include the output component (e.g.,winding, armature, permanent magnet, output gear, etc.) along the innersurface (e.g., inner arcuate surface) of the inflator housing, whereinthe output component is directly coupled to the spindle nut.Additionally or alternatively, the inflation system can a hub caphousing supporting the output component, wherein the output componentcan be mechanically connected to the inflator (e.g., the pump, which canbe mounted anywhere on the hub or wheel exterior) by an ETM.

In a fourth embodiment, the inflation system leverages the firstvariation, with the inflator replacing (or mounted within) an axialsection of the hub (example shown in FIG. 20A-20C). The axial section ofthe hub is preferably the exterior portion of the hub barrel (e.g., thefront two inches of the hub barrel, the front several inches of the hubbarrel, etc.), but can additionally or alternatively replace anysuitable section of the hub barrel, replace an axial section of the hubbarrel and extend along the hub exterior surface between the studs(e.g., within the hub scalloping), or be otherwise arranged.Additionally or alternatively, the inflator can be used instead of asnap ring to retain the spindle nut. In this embodiment, the inflatorcan include the output component (e.g., output gear, winding, armature,permanent magnets, etc.) coupled to the spindle nut (e.g., directlydriven, indirectly driven via an ETM). Additionally or alternatively,the output component can be mounted to the interior surface of the hub,or be otherwise retained. In this embodiment, the studs can extendthrough the inflator housing into the hub body, such that the inflatorhousing is sandwiched between the hub cap and the hub body. Additionallyor alternatively, the inflator housing can be retained in any othersuitable manner.

In a second variation of the inflation system, the inflation systemcaptures relative motion between the bearing spacer and the hub barrel(e.g. the inner diameter of the lubricant reservoir). In this variation,the bearing spacer is modified with the input component and the outputcomponent is mounted (directly or indirectly) to the hub barrel(examples shown in FIGS. 24, 20, 31, and 32). Alternatively, theinflator can be mounted to the bearing spacer, wherein the inputcomponent is statically mounted to the hub barrel (e.g., lubricantreservoir interior). The bearing spacer can be manufactured with theinput component (e.g., as a unitary component), or be retrofit with theinput component, wherein the input component is assembled over and/ormounted to the bearing spacer (e.g., using an interference fit,adhesive, retention mechanisms, etc.) before bearing spacer assemblyinto the hub. The input component can be an input gear (e.g., a collarwith external teeth, a bearing spacer modified with external teeth alongan axial section of the bearing spacer), inner stator, or any othersuitable input component. The inner stator can be a ferrous toothedgear, include windings, include permanent magnets, or include any othersuitable generator component. The input component is preferably arrangedcircumferentially about the bearing spacer's arcuate surface (or aportion thereof), but can additionally or alternatively be arrangedalong an axial surface of the bearing spacer or along any other suitableportion. The input component preferably extends along a portion of thebearing spacer length, but can alternatively extend along the entiretyof the bearing spacer length.

In this variation, the output component is preferably mounted to (orintegrated within) the interior of the hub barrel (e.g. the interiorsurface of the lubricant reservoir), but can alternatively be mounted tothe exterior of the hub barrel. The outer component can be mounted tothe interior surface of the lubricant reservoir, be mounted to orintegrated within the lubricant cap, or otherwise arranged.

The output component can encircle the inner component (e.g., becircumferentially or concentrically arranged about the inner component),be mounted to and/or couple to an arcuate segment of the lubricantreservoir (e.g., to a point within the lubricant reservoir), be mountedto an axial segment of the lubricant reservoir, or be mounted to anysuitable portion of the lubricant reservoir. In a first example, theoutput component can be an outer rotor that encircles the inner stator.The outer rotor can include field coils, armature windings, permanentmagnets, or any other suitable generator component. In a second example,the output component can include an idler assembly mounted to a pointwithin the lubricant reservoir. The idler assembly can include an outputgear that meshes with the input gear of the input component. In thisexample, the output gear can be mechanically connected to the inflatorvia a rotary-to linear-converter; be connected to an electricalgenerator mounted to the hub interior (e.g., to the lubricantreservoir), wherein the electrical generator is electrically connectedto the inflator; or be connected to any other suitable component.Additionally or alternatively, this variant can generate electricity byleveraging the existing magnet in the lubricant reservoir (e.g., forchip removal and/or collection) by modifying the bearing spacer withwindings or armatures (e.g., wherein the modified bearing spacer oroutput component on the bearing spacer generates electricity when thewindings or armatures pass by the magnet). This alternative canoptionally include an ETM that extends through the axle, along thebearing spacer-axle interface, to the inflator (e.g., at the hub end, atthe hub exterior, etc.), include a rotary junction, or include any othersuitable ETM. For example, the inflator or inflation system can includean electrically conductive collar statically mounted to the hub barrel,offset from and electrically connected to the output component (e.g.,via brushes), that conduct electricity from the modified bearing spacerto the electrically conductive collar (and subsequently, the inflator).In operation, wheel rotation about the axle causes the output componentto rotate about the modified bearing spacer. In a fifth embodiment ofthe second variation, the inflator is mounted to the hub face. In thisvariation the inflator can additionally include an ETM extending axiallythrough the hub barrel from the output component to the inflator at thehub face. The ETM can extend through the hub face, (e.g. hubcap),through a stud or through any other suitable component. The ETM canoptionally extend into a recess within the inflator housing. In thisembodiment the inflator can be directly driven by the output componentor include a rotary to linear converter inside of the inflator. Thisembodiment can be assembled by inserting the output components throughthe lubricant hole and mounting the output component to the hub barrelinterior (e.g. with adhesive screws or any other suitable mountingmechanism, et cetera), inserted in pieces through the hub rear (e.g.before inner bearing assembly to the hub rear and assembled within thehub cavity) and serve as a single piece through the hub rear orotherwise assembled. The input component can be manufactured with thisbearing spacer or fitted to the bearing spacer before bearing spacerassembly into the hub cavity. The inflator can be bolted to the hub facewherein the ETM can align with the protrusion or recess in the inflatorhousing at a complimentary connection point.

In a sixth embodiment, the inflator system leverages the third variant,and the inflator is located within the lubricant reservoir (exampleshown in FIG. 23 and FIG. 24). In this embodiment, the inflator ispreferably a toroid, circumferentially surrounding the bearing spacer,but can be otherwise configured. In this embodiment, the inflator can bemounted to the hub barrel (e.g. to the lubricant reservoir's interiorsurface, to the lubricant hole seal, etc.), or otherwise mounted to thelubricant reservoir interior. The input component is preferablystatically mounted to the bearing spacer, and the output component canbe statically mounted to the lubricant reservoir interior or be mountedto a component statically mounted to the lubricant reservoir interior.The inflator is preferably separated from the bearing spacer by a gap,but can alternatively be directly connected to the bearing spacer. Theinflator is preferably axially offset from the input component and/orthe output component, but can alternatively be coaxially arranged withthe input component and/or output component. In a first example, theinflator houses the output component along an inner diameter, and isaxially aligned with the input component. In a second example, theinflator houses the output component along a side face, and is axiallyoffset from the input component. In a third example, the outputcomponent is mounted to an intermediary component, wherein theintermediary component transfers the energy to the inflator (e.g.,axially offset from the input and output components). However, theinflator can be otherwise arranged. In this embodiment, the tireconnection can extend through the lubricant hole, a stud, or through anyother suitable path. In this embodiment, the inflation system can beassembled by feeding the inflator through the lubricant hole or throughthe back of the hub before assembling the inner bearing. However, thisembodiment can be otherwise assembled.

In a seventh embodiment, the inflator system leverages the thirdvariant, and the inflator is mounted along an exterior surface of thehub barrel (e.g. along an exterior arcuate surface, radially inward ofthe drive studs). In this embodiment the inflator extends axially(examples shown in FIGS. 25, 26, and 27), but can additionally oralternatively extend radially or in any other suitable direction. Inthis embodiment, the inflator can connect to the lubrication reservoircavity via the lubrication hole or a hub barrel pass through. In thisembodiment, the inflator can optionally function as the lubrication holeseal, wherein the inflator housing optionally includes a gasket 480 orother sealing component. In this embodiment, the output component ispreferably mounted to the inflator (e.g., the interior surface of theinflator), but can additionally or alternatively be separate from theinflator and connected to the inflator by an ETM. The output componentcan be an output gear, a set of windings, and/or be any other suitablePPA component. The output component is preferably axially aligned withthe inflator, but can additionally or alternatively be radially alignedwith inflator or otherwise aligned with inflator.

In an eighth embodiment, the inflator system leverages the thirdvariant, and the inflator is mounted to the wheel face (e.g. to thespokes), the hub end (e.g., form a hubcap, couple over the hub end,replace a section of the hub front, etc.), and/or any other suitableportion of the wheel end (examples shown in FIGS. 28, 29, 30, 31, 32,and 33). In this embodiment, the pump can be arranged such that the pumpaxis extends parallel with the wheel face (e.g., radially, along achord), but can additionally or alternatively extend in any othersuitable direction. In this embodiment, the inflation system can includean output component (e.g., an output gear, electrical generator, rotor,etc.) mounted to the lubricant reservoir interior (e.g., to thelubricant hole cap, the lubricant reservoir interior, etc.) and an inputcomponent (e.g., input gear, permanent magnet array, etc.), mounted tothe bearing spacer. In this embodiment, the inflation system canoptionally include an energy transfer mechanism that extends from thelubricant reservoir interior to the inflator (e.g., hub end, wheel end).The ETM can extend through a stud, a stud bore, function as a stud bore,through the housing between hub bores, out a radial section of the hubbarrel and along the hub exterior, or be otherwise arranged. The ETM ispreferably aligned with the output component, but can be otherwisearranged.

In a third variation, the inflation system captures relative motionbetween the bearing spacer and the hub barrel (e.g. the interior of thelubricant reservoir) using a plate as the input component (example shownin FIGS. 35A-35D). In this variation, the plate can be mounted to thearcuate surface of the bearing spacer and extend radially outward fromthe bearing spacer. The plate can be angled at a non-zero angle to thebearing spacer (e.g. angled at a non-perpendicular angle to the axleaxis, arranged perpendicular the axle axis, etc.). The plate can have aprofiled face (e.g., wherein the idler arm can be coupled to theprofiled face), profiled edges (e.g., wherein the idler arm can becoupled to the profiled edges), planar face, smooth edges, or beotherwise configured. The output component can include one or more idlerarms, contacting the plate at one end and connected to the pump pistonat an opposing end. The idler arms preferably extend axially (e.g.,parallel the axle axis), but can additionally or alternatively extend atan angle to the axle axis or in any suitable direction. The idler armsof the output component can slide along the plate face, hook onto theplate edge, or otherwise contact the input component. The inflationsystem can include one or more pump assemblies.

In this variation, the pump assemblies can be housed in the hub barrel(e.g., modified to mount the pump assemblies therein; include pump boresbetween the stud bores; etc.), be housed in the stud bores (e.g.,wherein the pump assemblies can be housed in the studs or replace thestuds and function as the stud bores), be mounted at the wheel end(e.g., wherein one or more ETMs extend through the hub housing, such asthrough the stud bores, to connect the idler arms to the pumps), or beotherwise mounted. The pump assemblies can be arranged with the pumpaxis parallel the axle axis, perpendicular the axle axis, or at anysuitable angle relative to the axle axis.

In this variation, the plate can be split and assembled around thebearing spacer from the back of the hub, before inner bearing assembly;can be manufactured with the bearing spacer as a singular piece; or beotherwise assembled into the hub.

This variation can optionally include a SEM. SEM can selectivelydisengage the output component from the input component (e.g. plate) bymoving the pistons to a compressed position, moving the plate axiallyaway from the pistons, moving the plate to a position perpendicular tothe axle axis or otherwise selectively engaging or disengaging the PPAcomponents. The SEM can be used to: selectively engage or disengage allpumps, a subset of the pumps, or any suitable number of the pumps (e.g.,to selectively adjust the pump rate and/or pressure). Additionally oralternatively, the pump rate can be adjusted by adding or removing pumpsinstalled into the hub and connected to the plate.

In third variant operation, wheel rotation about the axle causes theoutput component (e.g., idler arm(s)) to move along the plate, whereinplate features along the rotation path axially actuate the outputcomponent. The idler arms are connected to the pump pistons, which areaxially aligned with the idler arms, such that the idler arm axialactuation (due to changes in the axial position of the plate-coupledidler arm end) drives pump actuation.

In a fourth variant, the system uses an eccentric mass and bindingfriction. In variants, the system can include a cam that passively bindsthe spacer or axle component (e.g., via friction). In these variants,cam can rotate (e.g., “walk”—an example is shown in FIG. 45) around thespacer harmonically, due to the difference in diameters of the spacerouter diameter and the cam inner diameter.

In a first example of the fourth variant, the PPA includes an eccentricfloating cam with a lobe and a dimple (e.g., arranged in a low-slopearcuate region of the floating cam). In a specific example, the floatingcam can include a single lobe and a dimple diametrically opposing thelobe. The dimple has a dimple depth (e.g., 1 cm), extending radiallyinward on the follower surface of the floating cam. The system canadditionally include a stopper (hard stop), arranged proximate thepiston head on a radially inward portion of the pump, which prevents thepiston head from bottoming out on the radially inward portion of thedimple (e.g., from extending beyond the dimple bottom, from contactingthe dimple bottom, extending beyond 0.75 cm radially inward of itsposition at bottom dead center of the cam during pumping mode). Duringthe non-pumping mode 510, the piston head engages the stopper, and thecam follower engages the dimple at a depth less than the dimple depth(e.g., 0.75 cm), such that the cam rotates with substantially the sameangular frequency as the pump about the axis of rotation. During thepumping mode 500, the cam follower disengages the dimple and the cambegins to walk relative to the piston (rotating about the axis ofrotation with a different angular frequency than the pump, an example ofwhich is shown in FIG. 45).

In a second example of the fourth variant, the SEM includes an activefriction member separate and distinct from the pump (e.g., secondaryactuator 109), which controls the friction between the cam and thebearing spacer.

In a third example of the fourth variant, the pump is charged withpressurized working fluid (e.g., from the tire) to change the frictionbetween the cam and the bearing spacer.

In a fifth variant, the system uses binding friction (e.g., only) and noeccentric mass.

In a first example of the fifth variant, the PPA includes a symmetricfloating cam with two lobes with dimples arranged at bottom dead (onedimple per lobe). Each dimple has a depth of 1 cm, extending radiallyinward on the follower surface of the floating cam. A stopper (hardstop) prevents the piston head from extending beyond 0.75 cm radiallyinward of its position at bottom dead center of the cam (during pumpingmode). An example of the pumping stroke, max travel of the cam follower,engagement depth of the follower in the dimple, and depth of the dimplerelative to the cam is shown in FIG. 50.

Variants of the fourth and fifth variant can optionally be arranged atthe wheel end (e.g., used instead of the hubcap, mounted to the hubcap,mounted to the spindle, mounted to the spindle nut stack, mounted to anauxiliary shaft extending from the spindle or spindle nut stack,arranged axially outward of the spindle nut, etc.). For example, thefloating cam can fit over the spindle or a shaft extending from thespindle or spindle nut stack. These variants can be used for staticaxles (e.g., steer or trailer hubs), drive axles, and/or any othersuitable axle.

In a sixth variant, the system uses an active member to create frictioninstead of binding.

In variants, the cam would be forced to spin with the pump when pumpingis not needed. For example, the friction force can be removed so thatthe cam became free to spin (e.g., in the active friction variant).However, the cam can be actuated axially or radially; a divot on the lowpressure side that receives the roller if the pump is forcefullypressurized so that it extends beyond Bottom Dead Center (e.g., thedivot serves to interfere with the roller so that the pump will carrythe cam with it as it rotates with the hub); the pump has integratedhard stops (e.g., so that it doesn't transfer pressure force to the cam,when a cam is used); or otherwise statically engaged with the pump whenpumping is not needed.

Embodiments of the system and/or method can include every combinationand permutation of the various system components and the various methodprocesses, wherein one or more instances of the method and/or processesdescribed herein can be performed asynchronously (e.g., sequentially),concurrently (e.g., in parallel), or in any other suitable order byand/or using one or more instances of the systems, elements, and/orentities described herein.

As a person skilled in the art will recognize from the previous detaileddescription and from the figures and claims, modifications and changescan be made to the preferred embodiments of the invention withoutdeparting from the scope of this invention defined in the followingclaims.

We claim:
 1. A hub-integrated inflation system for an axle on a vehiclewith an axle spindle defining an axis of rotation, the hub-integratedinflation system comprising: a hub body defining a lubricant cavity; abearing spacer, arranged within the hub body, that is circumferentiallymounted to the axle spindle; a floating cam arranged within thelubricant cavity, the floating cam defining: a follower surface; aconcave reference surface arranged radially inward of the followerreference surface, wherein the concave reference surface contacts anouter surface of the bearing spacer over a contact area andcooperatively defines a gap with the outer surface of the bearingspacer, wherein the gap is diametrically opposed to the contact areaacross the bearing spacer; a pump mounted to the hub body; and a camfollower mechanically coupled to the pump; wherein the hub-integratedinflation system is operable between: a pumping mode, wherein the pumpis mechanically coupled to the bearing spacer via the cam follower andthe floating cam; and a non-pumping mode, wherein the pump is decoupledfrom the bearing spacer.
 2. The hub-integrated inflation system of claim1, further comprising a selective engagement mechanism, wherein a normalforce exerted by the floating cam on the bearing spacer is larger in thepumping mode than in the non-pumping mode, wherein the selectiveengagement mechanism changes the normal force exerted by the floatingcam on the bearing spacer.
 3. The hub-integrated inflation system ofclaim 2, wherein the follower surface defines a concave dimple, whereinthe selective engagement mechanism further comprises a stopperprecluding radial extension of the cam follower beyond a bottom of thedimple.
 4. The hub-integrated inflation system of claim 1, wherein apump interior is fluidly connected to a hub exterior in a non-pumpingstate, wherein the pump interior is fluidly connected to a tire interiorin the pumping mode.
 5. The hub-integrated inflation system of claim 1,wherein the hub body defines a pump cavity extending through a radialhub thickness, wherein the pump is arranged inside the pump cavity. 6.The hub-integrated inflation system of claim 5, wherein the hub bodyfurther defines a lubricant fill hole extending through the radial hubthickness, wherein the pump cavity is separate and distinct from thelubricant fill hole.
 7. The hub-integrated inflation system of claim 1,wherein the floating cam defines a set of lobes.
 8. The hub-integratedinflation system of claim 1, wherein the floating cam is disengaged fromthe bearing spacer in the non-pumping mode.
 9. A hub-integratedinflation system for a vehicle, the hub-integrated inflation systemcomprising: a hub body defining an axis of rotation, the hub bodyconfigured to rotatably mount to a static axle component; a camencircling the static axle component, the cam defining: an innerreference surface defining a central axis parallel to and offset fromthe axis of rotation; and an asymmetric follower surface arrangedradially outward of the inner reference surface; an output componentmounted to the hub body; and a cam follower selectively connecting theoutput component to the follower surface.
 10. The hub-integratedinflation system of claim 9, wherein the output component comprises apiston pump.
 11. The hub-integrated inflation system of claim 9, furthercomprising a selective engagement mechanism configured to selectivelystatically retain the cam relative to the hub body.
 12. Thehub-integrated inflation system of claim ii, the selective engagementmechanism comprising at least one dimple, the dimple arranged proximatethe follower surface, the dimple located at a local minimum of a radialthickness of the cam.
 13. The hub-integrated inflation system of claim9, wherein the inner radius of the floating cam is larger than an outerradius of the static axle component.
 14. The hub integrated inflationsystem of claim 13, wherein the inner reference surface and the staticaxle component each define circular cross sections.
 15. Thehub-integrated inflation system of claim 13, wherein the static axlecomponent comprises a bearing spacer coaxially aligned with the axis ofrotation.
 16. The hub-integrated inflation system of claim 9, whereinthe cam follower is arranged radially inward of the follower surface.17. The hub-integrated inflation system of claim 9, wherein the systemoutputs a torque of less than 50 inch-ounces on the output component.18. The hub integrated inflation system of claim 9, wherein the staticaxle component comprises a static axle spindle.
 19. The hub integratedinflation system of claim 9, wherein the cam is freely rotatable aboutthe static axle component.
 20. A system, comprising: a vehiclecomprising an axle spindle, the axle spindle defining an axis ofrotation; a hub body, the hub body configured to rotatably mount a wheeland a tire to the axle spindle about the axis of rotation, the wheelconfigured to rotate with a first angular frequency; a piston pumpradially mounted to the hub body; a cam defining: a circular innerarcuate surface encircling the axle spindle, the inner arcuate surfacedefining a central axis offset from the axis of rotation; and anoncircular outer arcuate surface defining a set of lobes, the outerarcuate surface configured to rotate with a second angular frequencydifferent from the first angular frequency; and a cam followerselectively connecting to the outer arcuate surface to the piston pump.